Viking1066
Chief Master Sergeant
Going by the author of the publication. Could be an error on his part. Anything is possible.
Original PBM: The original PBM was a seaplane with no landing gear.
PBM-5: The PBM-5 was not an amphibious aircraft and did not have retractable landing gear.
PBM-5A: The PBM-5A was an amphibious aircraft with retractable landing gear. The Navy ordered 36 PBM-5A models to address the PBM's lack of landing gear. The PBM-5A was used in the Coast Guard as the PBM-5G.